[llvm] AMDGPU: Migrate more tests away from undef (PR #131314)

[Pierre van Houtryve via llvm-commits]

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@@ -1511,7 +1511,7 @@ define amdgpu_kernel void @test_preserve_condition_undef_flag(float %arg, i32 %a
 ; GFX1064-NEXT:    s_endpgm
 bb0:
   %tmp = icmp sgt i32 %arg1, 4
-  %undef = call i1 @llvm.amdgcn.class.f32(float poison, i32 undef)
+  %undef = call i1 @llvm.amdgcn.class.f32(float poison, i32 0)
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Pierre-vh wrote:

Why use 0 here? Is this another test that depends on undef =/= poison?

https://github.com/llvm/llvm-project/pull/131314